Window units vs. portable a/c units.

What do we know about which is better or what are the pros and cons?

One is portable,but needs access to a window and a drain.  The other sits in a window and drains outside.  

^^ That's about it. 

We just had to replace a window unit last week. The portability is about the only advantage of the portable units, you get a bit more BTU/$ and better efficiency with a window unit. My dream eventually, though, is to get the whole house on a mini split system. 

I run a portable unit that self evaps so i dont have to drain it.  I run one because of my weird shaped windows where the opening is only 14-18" tall but 4ft wide.

The portable units can be put close to where you are or where you need the cooling so long as you can get the ducting to a window or vent of some sort.  Also, the portability can be nice if you don't need two rooms cooled at the same time -- you could cool the bedroom of a cabin overnight while sleeping and then move it to cool the living area during the day, for example.  

The draining is a problem.  Most of them can be set up to drain to a hose or to an internal tank.  The hose drains that I've seen aren't fully enclosed so if your hose pushes back for any reason -- clog, it goes slightly uphill, etc -- the condensate will balk the queue at the hose connection and just drip over the side.  If you're using the tank, it can be tricky to empty without spilling if it fills up.  And in either case, you can get condensate leakage if it's not perfectly level.

Another advantage of the window unit is that all the hot parts are outside.  With the portable, it will vent hot air out the tube, but the tube radiates some heat into the room as it snakes to the window and the unit itself will be a few degrees over ambient.

I’ve had a couple of portables and some very inexpensive window units. The portables were off of Craigslist, the window units new. 

I much prefer the window units. They’re more efficient and take up less space... as in, zero space. They work wonderfully. We bought them when our central ac went out last summer. Sitting in the basement now, but I’m not getting rid of them and actually should probably throw the one of them in the upstairs bedroom. 

One of our portables has to have a hose hooked up as a drain unless we want to empty the tiny bucket every hour. 

That being said, the other portable just has a single exhaust and lets the water vapor go through that. It keeps a few rooms cool enough, and is still in use in my parents vacation home that has casement windows. 

Thanks guys, that is the type of info I was trying to learn. Most of my experience is with central a/c. So, all of this helps. It looks I would be better with window units in my current situation.

Would I be better off with a whole house sized unit or two smaller units?

I prefer two smaller units, for both cost and cooling. Unless you have a very open floor plan, I’ve just never had a window (or through-wall unit) get to enough rooms. This was in college though, and not my units, so YMMV. 

I know the first place my wife and I rented had one whole house unit, but it would almost freeze you out of the living room in order to keep the bedrooms cool. That was not an open floor plan and was 20 yrs ago. I was not sure if they had improved since then. Thanks for all the info.  It is great that this board can answer questions quickly and thoroughly.

Definitely window units.  Definitely more than one.  Name brand 5000 BTU units can be had for under $100.  I'd suggest one for each bedroom, and a larger one for the living/dining/kitchen area.

Modern AC vents the water with the hot air (no more dripping AC units)  I have actually recommended this to several clients over the last couple years as the older units stain the masonry and if left in place long enough will actually damage it.

I agree with several smaller units.  Modern AC is much more efficient than those of even just a couple years ago.  We run small units in the bedrooms (each person can set it to there own temp) and a large one up stairs in the main living area and another large one for the downstairs common area.  

Our setup keeps the whole house cool and more importantly keeps the humidity down much cheeper than my friend that has a whole house AC system that was retrofitted to his forced hot air heating system.  Ours lets us only cool the areas of the house that we want cool so in reality we are only cooling about 1/3 of the house at any given time with modern efficient AC units.  Much cheeper than cooling an entire house with the whole house system.  The only down side to it is that you have to take them out and store them and then put them back.  For the bedrooms I have kept the box's they came in and just put them in the box and set them on the floor of the closet.  I am told by the ladys of teh house that it makes a great place to set shoes.  For teh main rooms I have to remove them and store them in the basement.  However another benefit of modern AC units is that they are MUCH lighter than those of even 5 years ago so it really is not all that bad.  

We just bought 10 portable units for the plant. They are pretty good at blowing air directly onto the line workers. In a normal garage they would probably be pretty effective. In a brick plant they are less than ideal but better than nothing. For what it's worth, I can think of better ways to spend $2700